diff --git a/Gemfile b/Gemfile
index 39902f2..72d74e5 100644
--- a/Gemfile
+++ b/Gemfile
@@ -20,7 +20,7 @@ gem 'jquery-rails'
 gem 'json-jwt'
 gem 'mini_racer', '~> 0.2.6'
 gem 'pg', '~> 0.18'
-gem 'puma', '~> 3.0'
+gem 'puma', '~> 4.3'
 gem 'rack-timeout', '~> 0.4'
 gem 'rails', '~> 5'
 gem 'redis-rails', '~> 5'
diff --git a/Gemfile.lock b/Gemfile.lock
index 7842833..6febbdf 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -92,7 +92,7 @@ GEM
       activesupport
       aes_key_wrap
       bindata
-    libv8 (7.3.492.27.1-x86_64-linux)
+    libv8 (7.3.492.27.1)
     listen (3.0.8)
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
@@ -119,7 +119,8 @@ GEM
     pg (0.21.0)
     popper_js (1.14.5)
     powerpack (0.1.1)
-    puma (3.11.0)
+    puma (4.3.9)
+      nio4r (~> 2.0)
     rack (2.0.7)
     rack-mini-profiler (0.10.7)
       rack (>= 1.2.0)
@@ -265,7 +266,7 @@ DEPENDENCIES
   listen (~> 3.0.5)
   mini_racer (~> 0.2.6)
   pg (~> 0.18)
-  puma (~> 3.0)
+  puma (~> 4.3)
   rack-mini-profiler (~> 0.10)
   rack-timeout (~> 0.4)
   rails (~> 5)